This invention relates to the fabrication of integrated circuit devices and more particularly to a method of forming a convex charge coupled device in the manufacture of integrated circuits. 2. Description of the Prior Art
A MOS transistor is formed having an extremely long channel and with many, perhaps 1000, gates closely spaced between source and drain. Each gate electrode and the substrate form a MOS capacitor which can store charge. Charge can be transferred from capacitor to capacitor as soon as an appropriate voltage is applied to the electrodes sequentially. This configuration is called a charge transfer device (CTD) or a charge coupled device (CCD). Efficiency of charge transfer is a major concern in the fabrication of charge coupled devices. US Pat. No. 3,792,322 to Boyle et al describes a buried channel charge coupled device. US Pat. No. 3,924,319 to Mohsen describes the use of stepped electrodes in charge coupled devices.